Hose vulcanizing apparatus



Oct. 10, 1950 H. A. FREEMAN HOSE vULcANIzING APPARATUS Filed May 7, 1948 FLUID SUPPLY vAcuuM souRcE 'FIG.4

FIG. 2

FIC-3.3

N A .m R E wm WA. mm. O R A H ATTORNEY Patented Oct. 10, 195.0

PATENT P -OFFICE 2,525,652 Y Hosa t-vuLcANIzrNG APPARATUS Application VMay 7,

10 claims. (ql. 18e-el therein, has `been to encase the hose ina lead tube Aor jacket. This lead Ajacket is extruded as a `tube about the uncured or `green 'hosefby means of a conventional lead press land forms `the curing moldfor `the outer surface of the hose. Water under `pressureis then introduced `inta; `the lead jaoketed hose to provide the required internal pressure and While stored on reels, the hose is subjected `to stearnfin a `heater unit -until the cure `is completed, `after which the `iead is strippedloff the cured hose.

This conventional practie `is expensive in view of `the cost ,Lof the equipment andthenecessity `to employ skilled labor, particularly `when fthe annual production of such products is relatively small. Moreover, `a Lhigh percentage `of curing defects are traceable to difcultiesfarising inthe considered to be 1desirable todevelop some process to avoid `the necessity of using the lleadlpress.

As alternatives, `certain `methods `have been employed in recent years according to which internally reinforcedhose hasmbeen vulcanized by the diierential upressure type cure. According to `this yiprocedure, huid under pressure is admitted internally "of the assvcibllqed`` Unwired hose and `a heated curing medium at a slightly lovver pressure is Aalziplied externally af'conventional heater unit to complete `thecure. This process was found to produce @satisfactory product, but the cured hose was subject yto frequent blovvs,iblisters, and `other blemishes caused by A convenient form of apparatus embodying `the I teachings of the present invention isillustrated in the accompanying drawing in Whicht-Fig. 1

irepresents a vertical cross section through a if c .30 leading operation. As a result, ithaslloun'g been Qld L Freeman, Akron, 1Ohio, asienor t0 ation, Alkrm, Qhio, a corpora- 1948, seal No- 254681 Waal Theater mit acer/ieg the apparatus adsly employed lin' the practice of the strates` the bleeder coni nLsectiojn and broken n aemelifary illustration ai i V ejvvithLpartsfbroken i ,to slfqvvftlierlcn u ion.` Il shows a fr meneryriin 0 pared 110.56'- 1o .1; the refaence numeral l `isi-aafla glenerallye'the "asee' bly of apparatus employed infconpletingfthe v-u aniaationof braided `hose mesur? Theasse 1i" lcnrhprises weer uniti l in A@the uppeihost portion of fvvhich` is i dis- 7a supply 1 3 ieitending Alengthwise 'thereoflfor" intrdducingstealm under pressure jto the H i r i giisfconstrueteduin such a yvayqas to prof/ide alrarhejllwhich fearries a plurality lef imei e {Slisihiy Submited unonbrali 9 securedtol eitherlsiue "of marraine. nach of "edn'urnber may t, gft e' edI to'fbe i emergent-12 afa is prei/ideama a i cia-bj1@ receivingnrneasormreceptacl 12in Whichone end |3"`i5f the coiled oseilislinsrted." A similar receiving means rreceptacle'lw n the breeder S, tecrep' Aeinerme diS- eg ef the viewed bse leeder "connection l i f the presentinvention connection if" is adaptedfto 'receive thelotlier i end f5."of the coiledhose in themanner shown Yin Fig.' 1 of the dr'avvingf" A"conduit EE interconnects the receptacles'lZ and i4 Vof the bleede'r4 @lei/@tion 0n a some- Y portifd` internally of` the source of vacuum 26 which may take the form of a vacuum pump or the like (not shown). A pipe connection 2l secured to the receptacle I2 of the bleeder connection II also extends through the outermost wall of the heater unit 2 in substantially parallel relation to the pipe outlet I3. A conduit 22 is provided externally of the heater unit 2 for, connecting the pipe connection 2l to one side of the diaphragm valve 23. The diaphragm valve 23 is also connected as by means of a conduit 24 to a suitable uid supply 25 for supplying fluid such, for example, as air under pressure to the diaphragm valve.

A tube 26 extends through the outermost wall of the heater unit 2 and is connected at one end t the opposite side of the diaphragm valve 23 from that to which the conduits 22 and 24 are connected while the other endopens into the interior of the heater unit. The piping arrangement for the diaphragm valve 23 just described thus enables a careful control of the pressure of lthe fluid from the supply introduced into the l hose I6 by reason of the action of the steam pressure inside the heater unit 2 upon the diaphragm of the valve through the medium of the connecting tube 26.

Any desired differential between the air pressure inside the'hose I6 and the steam pressure inside the heater unit 2 acting on the exterior of the hose may be established by adjustably controlling the action of the diaphragm valve 23.

Before explaining the operation of the apparatus i of Fig. 1 in detail, it is desirable to consider first the construction of the bleeder connection I I illustrated in Fig. 2 of the drawing. The conduit i6 interconnecting the receptacles I2 and I4 of the bleeder connection I I is made up of a number of threaded nipples 21, 28, and 29 connected together by means of the T I1 and a union 36. One end of the nipple 21 is threaded into an internally threaded boss 3| on the receptacle I2 while the other end is threaded into the T I1. The nipple 28 joins the T I1 and the union 30. The nipple 29 connects the other end of the union with an internally threaded boss 32 on the receptacle I4.

A bore 33 extends through the internally threaded boss 3l and connects at its innermost end with a chamber 34 formed internally 0f the receptacle I2. A substantially identical construction is embodied in the receptacle I4. At one end of the chamber 34 in the receptacle I 2 is an internally threaded bore 35 into which is inserted a fitting 36. The fitting 36 comprises an externally threaded end portion 31 for engagement with the bore 35 andan integrally formed tube 38 for insertion in the end I3 of the hose ID.

The tting 36 is provided with a bore 39 extending throughout the length of the end'portion 31 and the integrally formed tube 38. One end of the bore 33 in the end portion 31 of the fitting as is provided with an internati thread @which is threadably connected to the pipe connection 2| when the several elements are assembled in the heater unit 2. The tubular portion 38 of the ttings 36 is adapted to extend axially of the internal bore 4I of the hose I0, the end I3 of which is inserted through the bore 42 in that portion of the receptacle I2 directly opposite the internally threaded bore 35. T A tting 43 identical to the fitting 36 is provided in the receptacle I4 for engaging the end I5 of the hose Il). The fitting 43, instead of receiving a pipe connection 2I in the end portion thereof corresponding to atenerse end portion 31 0f the fitting 36, has a pipe plug 44 inserted therein.

The green or unvulcanized hose ill, before the vulcanizing operation is begun, takes the form of the material illustrated in Fig. 3 in which a ribbed jacket 45 is loosely slipped over a braided or interwoven reinforcing ply 46 made up of a plurality of cords 41. The ply 46, in turn, encloses a tubular inner core 48. To facilitate the useA of the bleeder connection II, it is necessary to strip back a portion of the ribbed enclosing jacket 45 as indicated by the reference numeral 49 (Fig. 3) to expose a portion of the reinforcing ply 46 embodying the cords 41. The stripped portion 43 should be substantially equal in length to that of the chambers 34 of the receptacles I2 and I4 when the respective ends I3 and I5 of the hose I6 are inserted therein as indicated in Fig. 2.

After the ends I3 and I5 are inserted in place in the receptacles I2 and I4, respectively, a gum seal 56Y is applied about the end of each of the receptacles `surrounding the bore 42 through which each end of the hose is inserted. The seal 56 serves to prevent the entrance of the surrounding atmosphere into the chamber 34 under the influence of the vacuum supplied to the connecting conduit I6 during the operation of the apparatus. The cured hose 5I illustrated in Fig. 4 of the drawing represents a typical section of the hose following the vulcanizing operation and illustrates the thoroughness of the impregnation of the reinforcing ply 46 by the rubber contained in the ribbed jacket 45 and the tubular core 48 locking the individual cords 41 in place in the body of the finished hose and leaving a smooth internal passage extending axially thereof.

In the operation of the apparatus, the uncured hose I6 is introduced into the heater unit 2 and all the connections are made in the manner illustrated in Fig. l of the drawings as described hereinabove. A slight vacuum is then applied by means of the vacuum source 20 to the conduit I9. A vacuum is thus built up in pipe outlet I8, conduit I6, and chambers 34 of the receptacles I2 and I4 so as to draw any gases or moisture present or created during vulcanization in the exposed reinforcing ply 46 in the stripped portions 49 of the ends I3 and I5 of the unvulcanized hose I6 into the chambers 34. The vacuum is applied continuously throughout the cure. The gases and moisture which would, if not removed, create defects in the iinished hose are thus wicked out of the braided cord, released in the chambers 34, and withdrawn therefrom. Vacuum may or may not be necessary, depending on the hose make-up.

Steam is introduced through the supply line 3 to the interior of the heater unit 2 until the atmosphere therein is substantially completely saturated. Air or other fluid under pressure is simultaneously introduced l to the diaphragm valve 23 from the fluid supply 25 and a pressure is built up internally of the hose I0, the air being supplied by the pipe connection 2! and conduit 22 at a rate suicient to exceed the pressure of the steam internally of the heater unit 2 by approximately two pounds per square inch. This pressure differential is maintained throughout the entire curing operation. The pressure differential may be varied to nt the type of hose.

It will be readily apparent that as the steam pressure is built up within the heater unit 2, the diaphragm valve 23 being exposed to the atmosphere within the heater unit .by means of the site 26;, dit `spefaal ripari `.fidjiisricerca to admit air under pressue to thebore 4I of the hose I0, at any desired rate to maintainjany predetermined pressure differential between the inside and outside df the hose. It has been found that optimum conditions are achieved With a maximum air pressure of nity-two pounds employed in the hose IB for a corresponding fifty pound maximum pressure of steam employed in the heater unit. This pressure diilerential is; advantageously maintained until the completion of `the cure;` At the end of the curing operation, the "pressures are reduced from the maximum at the samedifferentials. p i l It will be understood that `certain modificaf tions may be made in the apparatus hereinabove described without in any Way departing from the spirit or scope of the invention. While `itis desirable that a slight vacuum `be applied tcthe bleeder connection l! to insure the maximum eiciency in the withdrawal of gases and moisture from the reinforcing ply 4G of the hose Il), it is possible with certain types and sizes of hose to simply vent the pipe outlet I8 to the outside atmosphere. In addition, various forms of diaphragm valves may Ibe employed in the combination of apparatus Without affecting the operation of the system. Moreover, other suitable forms of .bleeder connections than the bleeder connection Il may be employed to afford the suitable connections for the ends i3 and i5 of the hose with the supplies of iiuid and vacuum.

While in accordance with the Patent Statutes one best known embodiment of the invention has been illustrated and described in detail, it is to be particularly understood that the invention is not limited thereto or thereby, but that the inventive scope is donned in the appended claims.

I claim:

l. A bleeder connection for use in the diierential curing of hose and the like, said connection comprising a pair of hollow receiving means one for one end and one for the other end of the hose, said receiving means having a chamber therein to encompass at least a portion of the end of the hose; tubular means in one of the receiving means for insertion in one end of the hose, said tubular means being connected to a supply of fluid under pressure; a second tubular means in the other receiving means for insertion in the other end of the hose providing a substantially duid-tight seal therefor; conduit means interconnecting the chambers; and evacuating means connected to the conduit means.

2. A bleeder connection for use in the differential curing of hose and the like, said connection comprising receivingmeans for one end of the hose and receiving means `for the other end of the hose; means in one of the receiving means for introducing fluid under pressure to the intefl rior of the hose; means in the other receiving means providing' a substantially f1uid-tight closure for the interior of the hose; a chamber in each receiving means into which the end of the hose extends, said chamber encompassing the end of the hose; and means interconnecting the chambers for venting the same.

3. A bleeder connection for use in the differential curing of bose and the like, said connection comprising receiving means for one end of the hose and receiving means for the other end of the hose; means in one of the receiving means for introducing huid under pressure to the interior of the hose; means in the other receiving means providing a substantially uuid-tight closure for 65:, the interior' of the hose; acca-inter incase rea ceiving means into which the end of the hose extends, said chamber surrounding at least a portion of the hose end; conduit means interconnecting the chambers;- and means venting the chambers through the conduit.

e. A l:` le`eder connection for use in the diierential curing 0f hose and the like, said connectin c'riris'ing receiving means for one end 0f the hose and receiving means for the other end of thehose; means in one of the receiving means for introducing fluid under pressure to the inteiior of the hose; means in the other receiving means providing aA substantially fluid-tight cioe suie for the interiorfof the hose; a chamber in each receiving means into which the end of the hose extends, said chamber encompassing at least a portion of the 'exterior of the hose end; means providing an outlet for each chamber; a conduit l nriectihg the outlet means; and means connected to the conduit for creating a vacuum in the chambers.

5. A bleeder connection for use in the differential curing of hose and the like, said connection comprising receiving means for one end of the hose and receiving means for the other end of the hose; means in one of the receiving means for introducing fluid under pressure to the interior of the hose; means in the other receiving means providing a substantially fluidtight closure for the interior of the hose; a chamber in each receiving means into which the end of the hose extends, said chamber Surrounding the exterior of at least a portion of the hose end; a common conduit interconnecting the chambers in the receiving means; and means connected to the conduit for creating a vacuum in each. chamber.

6. A bleeder connection for use in the diierential curing of hose and the like, said bleeder connection comprising a receptacle for one end of the hose; a receptacle for the other end of the hose;

a chamber in each receptacle encompassing the exterior of the end of the hose inserted therein; means in one of the receptacles for introducing iiuid under pressure to the interior of that end of the hose inserted therein; means in the other receptacle for providing a substantially fluidtight closure for the interior of the hose at the other end thereof; a conduit interconnecting the chambers; and means connected to the conduit for evacuating the chambers.

7. A bleeder connection for use in the differential curing of hose comprising a receptacle for one end of the hose; a receptacle for the other end of the hose; a chamber in each receptacle encompassing the exterior of the end of the hose inserted therein; means in one of the receptacles and extending through the chamber therein for introducing uid under pressure to the inner core of that end of the hose inserted therein; means extending through the chamber in the other receptacle for providing a substantially fluid-tight closure for the inner core of the hose at the other end thereof; a conduit interconnecting the chambers; means connected to the conduit for evacui compassing the end of the hose inserted therein;`

tubular means in each receptacle extending through the chamber therein for insertion in the end of the hose disposed in said chamber; and means interconnecting the chambers of the receptacles.

9. In a hose vulcanizing apparatus a connection for the ends of the hose to be vulcanized, said connection comprising a pair of receptacles, one for reception of one end and the other for the other end of the hose; a, chamber disposed internally of each receptacle, said chamber encompassing the end of the hose disposed therein; a plug member in each receptacle; a generally tubular portion on the plug member extending through the chamber for insertion in the end 0f the hose disposed therein; and means interconnecting the chambers of the receptacles.

10. In a hose vulcanizing apparatus a connec tion for the ends of the hose to be vulcanized, said connection comprising a pair of receptacles, one for the reception of one end and the other for the other end of the hose; a male member of ged erally tubular form in each of the receptacles for insertion in an end of the hose; a chamber formed internally of each receptacle, said chamber encompassing the end of the hose therein and surrounding at least a portion of the male member; and means interconnecting the chambers of the receptacles.

HAROLD A. FREEMAN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 168,087 Forsyth Sept. 28, 1875 1,773,138 Gammeter Aug. 19, 1930 2,226,768 Harrison Dec. 31, 1940 

